Issue #8627: Fix "XXX undetected error" from unchecked PyErr_WarnPy3k return.
This is just a quick fix:  if the warning is turned into an exception, the
exception simply gets ignored.
diff --git a/Misc/NEWS b/Misc/NEWS
index 3378c5d..8608d03 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -13,7 +13,10 @@
 -----------------
 
 - Issue #8627: Remove bogus "Overriding __cmp__ blocks inheritance of
-  __hash__ in 3.x" warning.
+  __hash__ in 3.x" warning.  Also fix "XXX undetected error" that
+  arises from the "Overriding __eq__ blocks inheritance ..." warning
+  when turned into an exception: in this case the exception simply
+  gets ignored.
 
 - Issue #8748: Fix two issues with comparisons between complex and integer
   objects.  (1) The comparison could incorrectly return True in some cases